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531.
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Effluents from three liquid anaerobic digesters, fed with municipal sewage sludge, food waste, or dairy waste, were evaluated as inocula and nitrogen sources for solid-state batch anaerobic digestion of corn stover in mesophilic reactors. Three feedstock-to-effluent (F/E) ratios (i.e., 2, 4, and 6) were tested for each effluent. At an F/E ratio of 2, the reactor inoculated by dairy waste effluent achieved the highest methane yield of 238.5 L/kgVSfeed, while at an F/E ratio of 4, the reactor inoculated by food waste effluent achieved the highest methane yield of 199.6 L/kgVSfeed. The microbial population and chemical composition of the three effluents were substantially different. Food waste effluent had the largest population of acetoclastic methanogens, while dairy waste effluent had the largest populations of cellulolytic and xylanolytic bacteria. Dairy waste also had the highest C/N ratio of 8.5 and the highest alkalinity of 19.3 g CaCO3/kg. The performance of solid-state batch anaerobic digestion reactors was closely related to the microbial status in the liquid anaerobic digestion effluents. 相似文献
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从消除储罐泄漏点、加强日常管理方面阐述了如何做好氮封储罐泄漏治理与预防,并对加强储罐泄漏防治提出建议。 相似文献
536.
China’s economic growth has a serious impact on the environment and resources. How much real cost did China pay for its economic
growth? This paper estimates the monetary costs of resource depletion, environmental pollution, and ecological degradation.
The paper examines the geographic distribution of resource and environmental losses across 31 provinces. The findings allow
us to reach the following conclusions. First, the national cost of resource depletion, environmental pollution, and ecological
degradation in 2005 was 2.5 trillion RMB. It accounted for 13.5% of China’s gross domestic product (GDP). Secondly, the cost
of resource depletion, ecological degradation, and environmental pollution has a different spatial distribution. The cost
of resources depletion mainly distributes in the central area, the cost of environmental pollution is in the eastern area,
and the cost of ecological degradation lies in the western area. Thirdly, the cost of natural resources depletion is 1,672.5
billion RMB, accounting for 67.8% of the total cost of resource and environment. It indicates that economic development has
a high cost of resource depletion. 相似文献
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Effect of methylmercury on LPO levels, SH groups and activities of GSH-Px, SOD, XOD in liver of rats 总被引:1,自引:0,他引:1
LIU Jin |yu GUAN Ming SUN Zhi |wei LIN Xiu |wu CAO Peng |yuan MENG Xiang |dong 《环境科学学报(英文版)》2000,(Z1)
iththeintroductionofagriculturalandindustrialdevelopmentandimprovementofhumanlife ,environmentalpollutionbecomesmoreandmoreofconcernforpeople.MeHgisoneoforganiclipidsoluble ,heavymetallicpollutants.Althoughitsbiologicaleffectswerestudiedinmanyfieldsbyre… 相似文献